Filter drum screen fastening means



Dec. 12, 1950 R. COLLINS FILTER DRUM SCREEN FASTENING MEANS Filed Nov.6, 1948 mmvrox. nalml'qlfiw BY 1 ATTOR EY w My w m PHI a g Patented Dec.12, 1 950 UNITED STATES PATENT OFFICE 2,534,1 1 Q FILTER DRUM SCREENFASTENING MEANS Raymond B. Collins, 'Southport, com, assi'gnor to TheLummus Company, New York, N. Y., a corporation of Delaware ApplicationNovember 6, 1948, Serial No. 58,661 I to improvements in 2 Claims.- (Cl.210-202) space between the drum and the panel. In prior practice eithera solid partition strip has been used or one half of the partition striphas been left floating, restrained only by clips and positioning studs.In the first instance the removal of the backing plate requires removalof the partition strip. In the second instance the floating half of thepartition strip can be removed by pulling out all of the caulking, butthe tolerances required for this type of construction result in unevenspacing of the floating half of the partition strip in reference to thefixed half and excessive amounts of caulking are required to fill thespace between the two halves of the partition strip. Inequalities ofalignment of the partition strips frequently exist.

The principal object of my invention is to provide an improved means forsecuring filter sections to a rotary filter drum whereby quicker andeasier attachment and detachment of the cloth can be accomplishedwithout the loosening of the filter panel members.

A further object of my invention is to provide an improved form of panelmember for a rotary drum type filter in which one of the securingelements is permanently attached to the filter drum and the otherelement is permanently attached to the panel member whereby the panelmembers may be more quickly and positively sealed in position andwhereby a fixed spacing of the filter medium from the drum is assuredfor a uniform surface for the filter cloth.

' A more specific object of the invention is to provide a die formedsheet metal strip of U shape which may be permanently welded to the drumshell to serve as a division strip and a Z shaped member also of dieformed sheet metal integrally secured to the perforated plate panelmember, the sides of the 2 member and the U-shaped member cooperating tofixedly position the panel with respect to the drum.

Further objects and advantages of the invention will appear from thefollowing description of a preferred form of embodiment thereof taken inconnection with the drawings attached which are illustrative thereofandin which:

V Figure l is, a partial perspective view with parts bodiment of myinvention, the drum generally indicated at I0 is adapted to be mountedin a suitable housing, or vat not shown. In the usual manner, thematerial to be filtered is subjected either to a pressure or vacuum insuch a manner that the filter cloth indicated at i2 will serve toseparatethe filter cake from the filtrate. As shown, the filtrate isconducted away from the filter surface by suitable conduits M.

It is usual practice in a filter of this type, to provide individualfilter cloth backing panels generally indicated at [6 which may extendthroughout the length of the drum. A panel may consist of a perforatedplate covered with a coarse wire backing screen 20 which thus serves asthe support for the filter cloth I2. These panels 16, each of which isarcuate in form, are conveniently supported by stud blocks or supportingbuttons 22 projecting from the drum shell 24. This arrangement serves toform a filtrate chamber 26 which is subject to drainage by the conduitsId.

In order to secure the panels I6 to the drum shell 24 and to each otheralong the longitudinal edges, I prefer to use the structure shown inFigure 2. Each panel l6 has a securing strip 21 on one side, the otherside iGa being planar. The securing strip 21 is conveniently of dieformed metal and of generally 2 shape. The outer flange is welded as at28 to the panel i6 and the radial wall 21a and base 21b of the Z memberextend inwardly of the panel member [6. Inasmuch as the fiange portionof the Z member 21 overlies the edge of the panel member IS, the panelmember will be effectively held in position whether or not the parts areintegrated by welding.

Mounted on the drum shell 24 is a generally U-shaped division strip 30,such strip also being preferably of die formed metal. It has a laterallyoutwardly projecting lip or flange 30a, and radially extending sidewalls 30b and 300 extending from the base 30d. For manufacturingreasons, this division strip is preferably mounted on shim members 33which in turn are secured to the drum shell 24 as by welding. Thedivision strip and shims make a sealed edge for the filtrate chamber 26.

Mounting of the panel IS on the drum is acplace with the side wall 27aclosely engaging the radial wall 300 on the division strip. At the sametime, the base 272: of the securing strip engages and rests on the base301! or the division strip to afford a predetermined positionwithrespect to the drum shell 24. I

Sealing of the parts is accomplished by the use of caulking 32 which isgenerally of a soft metal such as lead. As the side walls 21a and 300are slightly inclined in a dovetailed manner, the seal will permanentlyhold the panels in a fixed position.

The cloth I2 may then be wrapped over the entire drum surface withsuitable folds extending into the remainder of the groove of thedivision strip. This cloth may likewise be held by caulking such as leadas shown at 34. A longitudinal pitch lock bar 36 having grooves 35a toreceive and space the ultimate wire binding 38 is then applied.

It will be appreciated that the strips 21 and 30 are suitablyproportioned to. provide proper clearance for the cloth and a minimum ofclearance for the caulking. It will also be seen that any panel may beseparately removed if desired and thatthe removal of the cloth does notrelease the panels. This is of importance for the filter cloth may bereplaced a number of times without requiring the removal of a panel.

Although the end construction of the panel I6 is not shown it may alsohave a Z shape member such as 21 which will engage a suitable basemember such as the drum shell 24 and be locked to the edge of the filterdrum as by caulking.

It will be appreciated that the filter panels may thus be removed andreplaced without the need of hold down clips, securing bolts, or weldingand the filter may thus be easily serviced in the field without specialequipment.

While I have shown and described a preferred form of embodiment of myinvention I am aware that modifications may be made thereto within thescope and spirit of the description herein and of the claims appendedhereinafter.

I claim:

1. In a drum type continuous filter of the class described, having adrum shell, a plurality of support buttons extending above and mountedon the drum shell, a series of substantially ill-shaped division stripsextending longitudinally of the shell and integrally secured thereto,the side walls of the divisions strips being narrower at the open endthan at the base to form a substantially dovetail recess, one of theside walls of the division strip being planar in a plane substantiallyperpendicular to the drum shell, the

other side wall of the division strip being provided with a laterallyprojecting flange substantially parallel with the drum shell andapproximately spaced from the drum shell the height of the support Ibuttons, rigid arcuate filter cloth backing panels extending betweeneach of the division strips, a Z-shaped member extending along one edgeof each of said panels and having a flanged portion overlying the edgeof the panel, the base and side of the Z-shaped member being closelyembraced against the base and the planar wall of the division strip,said panels being uniformly spaced from the drum shell by the supportbuttons, and of a width to be held under the fixed flange of thedivision strip and the flanged portion of the removable Z-shaped member,a caulking material engaging the free edge of the Z-shaped member andthe lower portion of thedovetail recess in the division strip, a filtercloth extending over said panels and into said dovetail recess engagingthe outer side of said caulking material, and separate caulking materialon top of said filter cloth and within the narrow opening of saiddovetail recess to independently retain the filter cloth on said filter.

2. A filter of the class described in claim 1 in which the Z-shapedmember is integrally secured along its overlapping edge to the panelmember, the base of the Z-shaped member being narrower than the openingin the division strip whereby the panel member may be inserted inposition without bending.

RAYMOND R. COLLINS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,134,703 Cobb Nov. 1, 19382,289,411 Denhard et al July 14, 1942

